تبیین مدل مفهومی شبکۀ سبز شهری از منظر علوم محیطی

رویکرد پدیده‌های شهری براساس اصول «ایجاد شبکه» است. شبکه‌سازی در جهت تعریف اصول و روابط تنظیم‌کننده بین عناصر و بهینه‌سازی عملکرد زیر سیستم‌های شهری است؛ از این رو، فضای سبز در شهرها عاملی برای ارتقای زیست شهروندان در قالب یک شبکه موردمطالعه قرار می‌گیرد. به‌طوری که با ایجاد مدل‌هایی بتواند عملکرد سیستم را بسنجد و اساس یک حوزۀ تحقیقاتی جدید را تحت عنوان شبکۀ سبز ایجاد کند. شبکه‌های سبز شهری موجب پشتیبانی از عملکردها و خدمات اکولوژیکی می‌شود که به برنامه‌ریزی برای آینده شهرها کمک می‌کند. هدف این پژوهش، این است که با توجه به برداشت‌های گوناگون از مفهوم شبکۀ سبز شهری مبتنی بر دیدگاه‌های مختلف علمی با استنباط و استخراج اهم ابعاد، رویکردها و نگرش‌های مرتبط با این حوزه، مدل مفهومی را نسبت به شبکۀ سبز شهری از منظر علوم محیطی تبیین می‌کند. این پژوهش، با استفاده از روش کیفی و تحلیل اسناد مکتوب با بهره‌گیری از تجزیه‌وتحلیل هم واژگانی به استنباط و ارزیابی ابعاد، رویکرد و نگرش‌های حاصل از دیدگاه‌های مختلف توجه کرده که از بررسی 205 منبع علمی معتبر طی 21 سال گذشته به دست آمده است. سپس اطلاعات با استفاده از ابزار تجزیه‌و‌تحلیل lca بررسی و به‌منظور تجزیه‌وتحلیل ارتباطات بین اطلاعات جمع‌آوری‌شده از نرم‌افزار spad استفاده شد. در گام آخر با تحلیل و بررسی علوم محیطی موثر با استفاده از نرم‌افزار vosviewer، مهم‌ترین ابعاد، رویکردها و نگرش‌ها مشخص شد. یافته‌های پژوهش نشان‌دهندۀ آن بود که مفهوم شبکۀ سبز شهری با سه علوم محیطی مطالعات شهری، جغرافیای شهری و علوم اکولوژی ارتباط مستقیم دارد و این علوم در شکل‌گیری مدل مفهومی برای ارائۀ تعریف و تصویری روشن از این مفهوم در راستای به‌کارگیری در برنامه‌ریزی زیرساخت سبز شهری تاثیر بسزایی دارد. نتایج تحقیق نشان‌دهندۀ آن بود که مطالعات شهری به مفاهیمی همچون حفاظت از فضای سبز موجود در شهرها، ایجاد فرم‌های جدید فضایی، ترمیم و نگهداری از اتصالات میان اجزای تشکیل‌دهنده و ... توجه می‌کند. در جغرافیای شهری توجه به اصول اکولوژیک موجود در شهرها، رفع نیازهای اکولوژیکی طبیعت و انسان، زندگی شهری و ... مفاهیمی اثرگذار هستند. در علوم اکولوژی به‌عنوان مهم‌ترین حوزۀ تحقیقاتی در باب مفهوم شبکۀ سبز شهری، به ارتقای پیوستگی در فضای سبز شهری، ایجاد و طراحی کریدورهای بهینه، توجه به پیوند میان اکوسیستم‌های بزرگ‌تر با اکوسیستم شهری و ... اشاره می‌شود. نتایج به‌دست‌آمده نشان‌دهندۀ آن است که مفهوم شبکۀ سبز شهری یک زمینۀ تحقیقاتی چند رشته‌ای، با بهره‌گیری از روش برنامه‌ریزی شهری پشتیبانی‌شده به‌وسیلۀ ابزارهای تصمیم‌گیری که قادر به مدل‌سازی زیرساخت‌های سبز به‌عنوان شبکۀ شهری است که از مناطق طبیعی و نیمه طبیعی شکل گرفته و به‌منظور توزیع برابر خدمات عمومی برای افزایش کیفیت زندگی و همچنین طیف گسترده‌ای از خدمات اکوسیستم و پایداری در شهرهاست.

explaining the concept of urban green network from the perspective of different sciences by developing a theoretical framework

abstractnetworking aims to define the principles and regulatory relationships between elements and optimize the performance of urban subsystems. urban green networks support ecological functions and services that can help planning for the future of cities. the purpose of this research was to explain a conceptual model for the urban green network from the perspective of science according to the various perceptions of the concept of urban green network based on different scientific points of view by inferring and extracting the most important dimensions, approaches, and attitudes related to this field. by using the qualitative method and analyzing the written documents through the same lexical analysis, this research inferred and evaluated different points of view. the information was analyzed using the lca analysis tool and spad software was used to analyze the relationships among the collected information by examining the effective environmental sciences. using the vosviewer software, the most important dimensions, approaches, and attitudes were determined. the findings of this research showed that the concept of the urban green network was directly related to the three environmental sciences of urban studies, urban geography, and ecological sciences. these sciences had a significant impact on the formation of a conceptual model to provide a clear picture of this concept in line with urban green infrastructure planning. urban studies deal with concepts, such as protecting green spaces in cities, creating new spatial forms, etc., in urban geography, paying attention to the ecological principles in cities, meeting the ecological needs of nature and humans, etc., as the effective concepts. ecological sciences are also mentioned as the most important research fields regarding the concept of urban green network to promote continuity in urban green spaces, create and design optimal corridors, etc. the results of this study showed that the concept of urban green network was a multi-research field. it appeared as a field supported by the urban planning method by means of decision-making tools, capable of modeling green infrastructure as an urban network formed from natural and semi-natural areas and was in line with the distribution of public services to increase the quality of life, as well as providing ecosystem services and sustainability in cities.keywords: urban green network, green infrastructure, green space, vocabulary analysis introductioncurrently, approximately 54% of the world’s population live in urban areas and this number is projected to reach about 70% by 2030 due to population migration from rural to urban areas (organization, 2019: 24). urbanization generally causes many environmental problems that are mostly associated with the destruction or degradation of green spaces (who regional office for europe, 2017: 112). cities with higher population densities have less green space. for this reason, the relationship of city dwellers with their living environments requires their adaptation to semi-urban areas without borders, fences, hedges, and physical or administrative constraints. they leave nature to go to the city and use it as an opportunity and improvement (narain, 2017: 147). therefore, increasing population and the need to meet human needs can lead to the expansion of the use of natural resources and transformation of many ecosystems into urban areas (ersoy et al., 2019: 310), which has increased the demand for land in many countries, especially in developing countries. with the increase in urban construction, the need for land and housing has led to land use change and non-land conversion. urban areas have become  a land for urban construction (tannier, 2016: 84). considering these issues, it can be said that urban green network has an important place for protection of biodiversity (angold et al., 2006: 202; karuppannan et al., 2014). methodologyto answer the questions, a collection of scientific articles from reputable scientific journals was analyzed by using lexical analysis tools. this approach made it possible to extract the main semantic dimensions in question in order to highlight the current meanings and practical contexts of the green network concept, especially from an urban planning perspective. to use this method, the data collection was performed in two different stages: 1) collecting highly cited scientific articles in the field of urban green infrastructure studies during the last 21 years and 2) selecting items that contained specific references to the concept of green network. the scientific articles were collected by searching in two scientific databases, scopus and google scholar. they were selected and filtered by using the main keyword (urban green space) and collected according to the number of citations. also, the collected information led to a conclusion for each of them by identifying the main keywords of each article and examining its key points. the data were analyzed using the analytical instrument of life cycle assessment (lca), which is an analytical tool that is able to identify the hidden meaning of a group of texts. this type of data analysis is basically based on &differences& (de falco et al., 2021: 198). spad software was utilized to analyze the relationships between the collected information, such as factors and components, each of which showed an aspect of the type of communication contained in the information. in this way, the analysis allowed us to examine whether the role of urban green space towards specific issues, such as urban green network, in the scientific community had been evolving. therefore, we could extract the main concepts that defined the stages of this evolution in the last 20 years. discussionextensive urbanization has made cities more complex than ever before. as a result, &new knowledge about cities& has emerged in the scientific debate and more advanced mathematical models, especially network models, have been developed to describe and optimize physical networks and human interactions. from this perspective, the elements of the natural environment in urban patterns can be also designed and managed as networks by integrating the findings of natural and social sciences into a multidisciplinary approach. therefore, increasing attention to the different roles that green space can play for the sustainable development of urban areas has made the scientific community include the concept of green network in their vocabulary. however, by analyzing the results of the present study, which was done by using lexical analysis tools, it was clear that the concept of green network was still semantically ambiguous and unclear. the reason for this confusion was first of all due to the meanings of two terms in the concept: &green and network&.